AAVSO: American Association of Variable Star Observers

Proposal #123

Proposer (15273) Surjit Wadhwa (surjitwadhwa@gmail.com) obscode: WMX
Assigned To(3663) Dirk Terrell
Date SubmittedNov. 17, 2019

Project: Identification of Bright Potential Red Nova Candidates.

Aim: To obtain and analyse (Wilson-Devenney) multi-band photometry of contact binary systems with features suggestive of potential red nova candidates being of low mass ratio and high degree of contact.

Subject Selection: Review of survey data (ASAS, ASAS-SN, Catalina etc) to identify contact binaries with likely complete eclipses (suitable for photometric analysis). Select systems with amplitudes below 0.45 magnitude (likely to be low mass ratio). Perform WD analysis of survey data (not accurate due to poor cadence and poor phase coverage) to obtain estimates of mass ratio and degree of contact. Systems identified as being likely low mass ratio (<0.2) and likely high degree of contact (>60%) shortlisted for formal photometry. Only systems brighter than 13 magnitude selected as these could be followed with modest instruments (amateur) to detect period changes in the future.

Over 40 potential systems have been identified mostly in the southern hemisphere and these are being observed with instruments located in Australia. The proposal is for observation of two potential candidates which are not accessible from the location of my instruments.

System 1: TYC 2449-2206-1 RA: 07 00 09.41 DEC: 35 41 49.3 Preliminary Mass Ratio ~0.14 Preliminary Fillout ~80%
System 2: TYC 4112-446-1 RA: 07 39 39.46 DEC: 61 16 36.3 Preliminary Mass Ratio ~0.11 Preliminary fillout ~65%

Given the magnitudes, the candidates would likely need to be observed from either Sonoita Research Observatory or New Mexico State University Observatory. As cadence of less than 5 minutes (prefer <3 minutes) would be required for accuracy I don't think the candidates are suitable for BSM. I would prefer multi-band (BVR) or at least dual band (VR or BV) full phase imaging. There is no real urgency however imaging within 6-9 months would be desirable.

At this stage I have not indicated exposure times and other acquisition parameters as I am not familiar with local conditions and instrument capabilities. I am happy to do so if required after studying the technical details of the instruments.

I hope the proposals meets with the approval of the TAC

Please contact me via e-mail - surjitwadhwa@gmail.com for any further information

Kind Regards
Surjit Wadhwa (WMX)

Target RA (H.HH) Dec (D.DD) Magnitude Telescope Observation Frequency Expiration Date Proprietary Term
TYC 2449-2206-1 7.002614 35.69703 11.8–11.4 1 Year
TYC 4112-446-1 7.660961 61.27675 11.82–12.15 1 Year


(1573) David Cowall — Dec. 18, 2019, 9:16 p.m.

deployed NH2 and NM

Comments on this proposal are closed.